I SWEAR I felt buzzed after drinking my first one too! I got GT's Passionberry Bliss. BUT I drank it right after an hour long workout, so I think that had a lot to do with it. Probably just endorphins or something in my case, but it was the closest to buzzed I've been in a long time lol. Gotta be careful.
I had the second half of the bottle the following day after a meal and felt fine. Probably was just the empty stomach.
Thanks for asking the question about home-brew! I was thinking of making my own and was concerned about the sugar you add to start the concoction. I'm on a very strict Whole30 budget, so I can't afford to buy $3+ bottles for every day. I like how my body reacts to it though